Low back pain (LBP) is strongly associated with opioid consumption among veterans, and improved clinical management of LBP is likely to reduce reliance on opioid among veterans. Up to 60% of patients with an acute episode of non-specific LBP experience either symptom persistence or symptom relapse within one year. This is likely an indication of a failure in addressing the underlying mechanisms of pain or initiation of a new etiology; both may stem from a mismatch between patients and treatments. The overall goal of our research is to develop, validate and implement measures that are relevant to known mechanisms of LBP, which can then be used to holistically gauge the health status of patients? lower backs beyond self-reporting of symptoms. More accurate measurements will help better match of patients with existing treatments or development of more effective new treatments. The specific objective of this study is to generate evidence in support of the feasibility of our methods for 1) the evaluation of relative contribution of lower back tissues to spinal loads, and 2) the investigation of the resultant spinal loads in veterans with non-specific LBP. We have developed a powerful set of tools for the comprehensive assessment of spinal loads and lower back mechanical behavior (MB), that will enable us to examine the existence or development of abnormalities in spinal loads and lower back MB in [five] groups of veterans with different experiences with non-specific LBP. These groups will include [1) veterans with chronic, non-specific LBP and high level of disability (n=10), 2) veterans with chronic, non-specific LBP and low level of disability (n=10),] 3) veterans with non-chronic, non-specific LBP (n=10), 4) asymptomatic veterans with a recent history (i.e., during the past year) of non-specific LBP (n=10), and 5) asymptomatic veterans without a recent history of non-specific LBP (n=10; serving as control group). Successful completion of this feasibility project will pave the way for future studies (merit grant applications) that will verify the role of abnormalities in lower back MB and spinal loads in the clinical presentation of LBP. Such an understanding has the potential to help the affected veterans with disabling non-specific LBP. Specifically, measures of lower back MB and spinal loads can be used not only to identify veterans with mechanical abnormalities in their lower back who are likely to experience LBP in the future, but also to guide novel integrated physical and psychological preventative treatments aimed at improved lower back mechanics. Ultimately, the goal and resultant improvement in clinical outcomes of treatment for non-specific LBP is to diminish reliance on opioids for the symptom management of particularly veterans with chronic LBP.